165
8
exclusively of amylopectin; amyl corn, on the
other hand, can contain 50–85% amylose. These
two variants are mutants which have been created by classical breeding of different corn varieties. Another way of increasing the proportion
of the desired amylopectin is to use genetically
modified varieties. The Amflora potato developed
by BASF is one such genetically modified species
that contains almost exclusively amylopectin.
After its interim approval in 2010 and several test
cultivation areas in Sweden, Germany and the
Czech Republic, BASF terminated the Amflora
project in the EU in 2012 due to some resistance
and lack of acceptance for genetically modified
plants.
8.2 Starch Production
The extraction of starch and the process steps
required for this heavily depend on the respective
crop. In principle, starch production begins with
the purification of the raw material by washing
and sorting out contaminants. In the next step,
BOX: A Brief History of Starch
The extraction and use of starch
can already be proven in ancient
times: In Egypt, papyrus strips
were attached to each other
with starch glue as early as
4000 BC. The Latin name for
starch (amylum) comes from the
Greek αμυλον (amylon). This
word means “not ground in a
mill”, because it was possible
to obtain starch powder from
wheat grains without having
to grind them beforehand.
The oldest description of the
production of starch originates
from the famous Roman Marcus
Porcius Cato (the Elder), who
may still be known to many from
Latin lessons due to his saying
“Ceterum censeo Carthaginem
esse delendam”. In his book “De
agri cultura” around 170 BC, he
wrote about starch production
(Amulum sic facito): “Well-cleaned
wheat grains are poured into a
hollow and watered twice a day
for 10 days. The swollen grains
are then pressed using linen
bags and the starch precipitated
from the press water is dried
in the sun”. The manufacturing
principle has remained very
similar to this day, even though
the apparatus technology used
has changed considerably in the
meantime.
In Europe of the 16th and 17th
century, starch was used to
stiffen white linen. In the high
society, it became popular to
stiffen linen collars and frills
with starch. This technique
was later used on the cuffs of
men’s shirts and on petticoats.
An advantage of the starched
lingerie is that dirt preferentially
accumulates on the starch in
the fabric and can therefore be
washed out more easily. Due to
this history, in German, the same
word for stiffening lingerie and
for the renewable raw material
is used: “Stärke(n)”. This word
later became the English word
“starch”.
At the beginning of the
19th century, the
chemical investigation of
starch finally began: In 1804,
the Frenchman BouillonLagrange first described the
production of dextrins (see
7 Sect. 8.4.1). In 1811, the
German pharmacist Constantin
Kirchhoff discovered at the
court of the Russian tsar the
acidic hydrolysis of potato
starch into glucose (see
7 Sect. 8.4.2).
In Europe, starch was originally
obtained exclusively from
wheat; later, it was also
obtained from potatoes and
corn. Today (2016) there are 77
starch factories in the European
Union producing 10.8 Mio. tons
of starch per year for which
17 Mio. tons of cereals and
11 Mio. tons of potatoes are
processed. In 2017, the global
starch market was estimated at
35.8 billion US dollars.
About 85 Mio. tons of starch are produced annually (2017), with the largest production capacities
in the USA, the EU, Japan and Thailand: 53%
goes into sweeteners, 36% into native starches
and 11% into modified starches. Out of these,
corn accounts for 68% of the modified starches
and the bulk of sweeteners are used as feedstock. In addition to the proportion of starch in
each plant, the composition of the starch, i.e. the
ratio of amylose to amylopectin, is important
for the industry; in most cases, amylopectin is
of particular interest. This is due to the fact that
amylopectin forms a highly viscous mass when
dissolved in hot water and does not gel like amylose. Aqueous amylopectin solutions are also
more stable during storage and do not crystallize.
This behavior makes amylopectin an interesting
and often more valuable raw material.
However, the separation of amylose and
amylopectin is only possible with great effort.
For this reason, cultivating plants that form the
desired raw material to a special degree or even
exclusively has long been a great effort. The
starch of waxy corn, for example, consists almost
8.1 · Structure and Occurrence
8
exclusively of amylopectin; amyl corn, on the
other hand, can contain 50–85% amylose. These
two variants are mutants which have been created by classical breeding of different corn varieties. Another way of increasing the proportion
of the desired amylopectin is to use genetically
modified varieties. The Amflora potato developed
by BASF is one such genetically modified species
that contains almost exclusively amylopectin.
After its interim approval in 2010 and several test
cultivation areas in Sweden, Germany and the
Czech Republic, BASF terminated the Amflora
project in the EU in 2012 due to some resistance
and lack of acceptance for genetically modified
plants.
8.2 Starch Production
The extraction of starch and the process steps
required for this heavily depend on the respective
crop. In principle, starch production begins with
the purification of the raw material by washing
and sorting out contaminants. In the next step,
BOX: A Brief History of Starch
The extraction and use of starch
can already be proven in ancient
times: In Egypt, papyrus strips
were attached to each other
with starch glue as early as
4000 BC. The Latin name for
starch (amylum) comes from the
Greek αμυλον (amylon). This
word means “not ground in a
mill”, because it was possible
to obtain starch powder from
wheat grains without having
to grind them beforehand.
The oldest description of the
production of starch originates
from the famous Roman Marcus
Porcius Cato (the Elder), who
may still be known to many from
Latin lessons due to his saying
“Ceterum censeo Carthaginem
esse delendam”. In his book “De
agri cultura” around 170 BC, he
wrote about starch production
(Amulum sic facito): “Well-cleaned
wheat grains are poured into a
hollow and watered twice a day
for 10 days. The swollen grains
are then pressed using linen
bags and the starch precipitated
from the press water is dried
in the sun”. The manufacturing
principle has remained very
similar to this day, even though
the apparatus technology used
has changed considerably in the
meantime.
In Europe of the 16th and 17th
century, starch was used to
stiffen white linen. In the high
society, it became popular to
stiffen linen collars and frills
with starch. This technique
was later used on the cuffs of
men’s shirts and on petticoats.
An advantage of the starched
lingerie is that dirt preferentially
accumulates on the starch in
the fabric and can therefore be
washed out more easily. Due to
this history, in German, the same
word for stiffening lingerie and
for the renewable raw material
is used: “Stärke(n)”. This word
later became the English word
“starch”.
At the beginning of the
19th century, the
chemical investigation of
starch finally began: In 1804,
the Frenchman BouillonLagrange first described the
production of dextrins (see
7 Sect. 8.4.1). In 1811, the
German pharmacist Constantin
Kirchhoff discovered at the
court of the Russian tsar the
acidic hydrolysis of potato
starch into glucose (see
7 Sect. 8.4.2).
In Europe, starch was originally
obtained exclusively from
wheat; later, it was also
obtained from potatoes and
corn. Today (2016) there are 77
starch factories in the European
Union producing 10.8 Mio. tons
of starch per year for which
17 Mio. tons of cereals and
11 Mio. tons of potatoes are
processed. In 2017, the global
starch market was estimated at
35.8 billion US dollars.
About 85 Mio. tons of starch are produced annually (2017), with the largest production capacities
in the USA, the EU, Japan and Thailand: 53%
goes into sweeteners, 36% into native starches
and 11% into modified starches. Out of these,
corn accounts for 68% of the modified starches
and the bulk of sweeteners are used as feedstock. In addition to the proportion of starch in
each plant, the composition of the starch, i.e. the
ratio of amylose to amylopectin, is important
for the industry; in most cases, amylopectin is
of particular interest. This is due to the fact that
amylopectin forms a highly viscous mass when
dissolved in hot water and does not gel like amylose. Aqueous amylopectin solutions are also
more stable during storage and do not crystallize.
This behavior makes amylopectin an interesting
and often more valuable raw material.
However, the separation of amylose and
amylopectin is only possible with great effort.
For this reason, cultivating plants that form the
desired raw material to a special degree or even
exclusively has long been a great effort. The
starch of waxy corn, for example, consists almost
8.1 · Structure and Occurrence